Dr. Seymour has served since 2016 on the Board of Trustees for the International Patient Organisation for Primary Immunodeficiencies (IPOPI). He has served since 2006 on the Board of Trustees for the Immune Deficiency Foundation (IDF) in the United States, serving as Chair from 2012-2021. Dr. Seymour has been a family therapist for over 40 years, with a focus on children, adolescents, and their families. Much of his clinical practice, university teaching, clinical supervision, and research has focused on resilience and coping with chronic illnesses. He is an Emeritus Professor and Distinguished Faculty Scholar at Minnesota State University, Mankato, where he taught for almost 20 years. He has continued his clinical practice after retirement from the University, working in a local outpatient mental health clinic. His previous professional experiences included several clinical, supervision, and administrative positions in a variety of healthcare settings and private practice.